Method and device for the measurement and the characterization, at high speed, of magnetic materials.

摘要

A process for characterization of magnetic materials for validating documents carrying marks which include magnetic materials is based on an analysis of signals supplied by an oscillator generating a low frequency signal supplying emitter windings and receiver windings that have different conformations. The receiver windings (A) and (B) are joined to an amplifier that has two outputs (S1) and (S2), output (S2) yielding, upon conformation, a signal (X) that is used as a time reference, and output (S1) yielding, after various transformations, two signals (Y) and (Z), each of which is entered into a microprocessor which, together with valid magnetic marker data, generate signals accepting or rejecting the document.